Electric heater.



W. UNDERWUOD.

ELECTRIC HEAI'ER APPLICATION FILED JAN 30,

Patented Fab. 16, 1915 2 SHHETS'SHEET 1.

W. B. UNDERWOOD.

ELECTRIC HEATER. APPLICATION FILED JAN. 30, 1914,

P.wz. Mm u mm "A "M mm W%% m 0 L m e 42, a

NITED STATES WEEDEN B. UNDERWOW, G! EKIE, BENNSXLVANLQ, ASSIGNO Paginnr OFFICE.

so AMERICAN commit, an rmxrsrnvaivra, a negro anion or PENN- mam Ewe-mic Brianna.

1,123,515.; specification of Letters Patent. p t t d b, 1 1915 Applicant-ten filed January 30, 1914. Serial Ho. 815,437.

To all whom it may concern:

.Be it known that I, Wnronn B. Unassyvooo, a citizen of the United States, res1ding at Erie, in the county of Erie and State of Pennsylvania, have invented new and useful Improvements in Electric Heaters, of which the following is a specification.-

This invention relates to electric heaters andconsists in certain improvements in the construction thereof as will be hereinafter fully described and pointed out in the claims. I

The invention is illustrated in the accompanying drawings as follows Figure 1 shows a central vertical section on the line 1-1 in Fig. 2. Fig. 2 a bottom view of the heater. Fig. 3 a diagrammatical view showing the method of connecting up the units with the terminals. Fig. 4 a side elevation, partly in section, of one of the units. Fig. 5 a cross section of a unit on the line 5-5 in Fig. 4. Fig. 6 an edge view, partly in. section of a. unit.

1 marks the heater case. Ahead 2 is secured in the end of this case by the screws 3, a gasket 4 being used to make a tight joint, the heater here shown being especially designed r heating liquids, as water in sterilizing, The electrical connections are mounted on the head 2 and it is, therefore, desirah .rry any drip there may be from away from. the terminals and conne id for this purpose I supply the lip .1 n s -eh extends beyond the head and is positioned to carry any drip past the head. The unit cases 6 extend through perforations 7 in the head and are secured therein so as to make a complete closure in any desirable manner. The posts 8 extend downwardly from the head 2 and the terminal support-s 99 are secured to these posts. The termi-. nal supports haye the bowed centers 10, thus forming an opening 11 between them through which access may be had to the ends of the units mounted. in the head. The ter' minal supports have the centrally located terminals 12 and end terminals 13 and 14. The resistor leads 15 extend from the units to these terminals.

Fig. 3 shows in diagram the met od of connecting up the leads with theterniinals. In the-heater shown there are eight nits 'forming two duplicate series each having units a, b, e and d. The terminal 14 is connected with the units a and 7) by the leads nerted with the terminal 13 by the leads 0" d and the opposite sides of said units are connected with the terminal 12 by the leads 0'' d These units may by proper switches be used in varying combinations and arrangcments so as to vary the capacity of the heater as desired. hese variations are increased by mounting'the two series together as this gives a nicer graduation as to heat capacities. By bowing the terminal supports access is given to the leads 15 throu h thw opening 11 and these leads can it brought to the terminals arranged on t e sides of the opening. Furthermore, if the headis circular as indicated in Figs. 1 and 2 this arrangement permits of as small a head as possible with a larger terminal. By spacing the terminal supports from'the heads the screws 3 can be brought under the terminal supports (see Fig. 2) where necessary thus decreasing the size of the head.

The detail construction of the units is shown in Figs. l, 5 and 6. An insulating piece 16 is provided with a series of slots 17 extending inwardly from its edge. resistor 18 is wound on this insulating core extending from slot to slot. This is a common method of winding such resistors. Two of such resistor coils are arranged in each unit, the insulating strip 19 being arranged between the coils. Insulating strips 20 are arranged outside the coils and next the case 6.

Considerable difliculty has been experienced heretofore in preventing excessive heating at the point where the resistor extensions connect with the leads. One of the principal objects of my invention is to correct this difficulty. Two resistor coils are connected by the connector lead 21. This is in the form of metal ribbon and is bent over forming a U-shaped strip. The ends are carried under the resistor coils and. between the outer wraps of the resistor coil and the The insulating core. This lead extends under a.

ends 21* of the connector lead 21 are bent 0 back upon the lead itsclfand woven under and over the wraps of the resistor as clearly shown in Fig. 6. The unit so formed is then subjected to pressure so as to bring the conof-the resistor. The terminal leads are seunit is in place so as to cured in the unit in the same manner as the connector leads 21, that is to say the terminal lead 15 is carried undera series of wraps of the resistor and the ends 15 turned back and woven under and over the wraps of the re,- sistor as clearly shown in Fig. 6 thus secur; ing the terminal lead in place and insuring pressure contact. This is made more certain y subjecting the case 6 to pressure after the have the case 6 exert pressure on the lead 15 just as in the case of the connector leads. The resistance of the resistor may be varied either by the connector lead or terminal lead as may be more convenient. It is desirable, however, to have both leads engage a plurality of wraps of the resistor.

What I claim as new is 1- 1. In an electric heater, the combination of a resistor having a series of transverse portions; and a resistor lead woven-into the resistor and engaging a plurality of transverse portions. I

2. In an electric heater, the combination of a resistor having a series of transverse portions; and a resistor lead extending past a plurality of said transverse portions and having its endbent back upon itself and woven into said transverse portions of the resistor.

3. In an electric heater, the combination ity of said transverse portions; and a unit a case arranged over said resistor and lead and exerting pressure thereon to efiect pressure contact between the resistor and lead.

5. In an electric'heater, the combination of a heater head in which two series of heater units are mounted; bowed terminal supports carried by the head and having an opening between them; terminals on sai supports; and leads from said terminals accessible through said opening.

6. In an electric heater, the combination (Elia heater head in which a series of units are mounted; terminal supports carried by the head and spaced therefrom; a heater case in which the head is mount-ed; and screws for securing the head to the case.

7. In an electric heater, the combination of electric units; a head in which said units are mounted; a terminal on the head in which the units are mounted; a heater case to which the head is secured, said case hav ing a lip extending past the head for carrying the drip away from the head.

n testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

WEEDEN B.) UNDERWOOD. Witnesses:

B. M. HARTMAN, V. C. Hnss. 

